Egg Drop Ideas: Solve the Physics Puzzle

[Maddyk]

Homework Statement

I need help with egg drop ideas! For this project, I have to create something that will catch an egg (about 62.5 g) dropped from a height of 9.91 meters so that it will not break or crack. I also have to discuss forces, impulses, momentum, time and velocity changes of the egg. I also have to calculate the work done by my device.

Homework Equations

p=mv
Ft=p2-p1
V=Vo+at
d=do+Vo+.5at
V^2=V(o)^2+2a(d-do)
W=Fd

The Attempt at a Solution

Well, for my contraption I know I need to increase the time the egg drops in order to decrease the force impacted on its shell. I was thinking of putting tissue paper in a box or even getting the tiny packing material and putting it in a box? I just wanted to know if anyone had any other solutions
As for solving for final velocity, I used V^2=V(o)^2+2a(d-do)=0+2(-9.8 m/s^2)(-9.91 meters)=194 m/s
I don't think that's right though…
As for the other equations, i can't solve for them until I decide what I will be making my apparatus from...

 

[Bystander]

I don't think that's right though…

It's not. You might want to check your "relevant equations" for starters.

 

[Maddyk]

It's not. You might want to check your "relevant equations" for starters.

Okay. I went over my notes again, and i used d=vt+1/2at^2 to solve for t (t=(2d/g)^1/2) being that g=a=-9.8, and i got 1.42 s for the time. Would I be able to plug that time into the Vf=Vo+at equation (a=-9.8) to get final velocity? I did that and got -13.9 m/s

 

[Bystander]

Much better.

 

[Doug Huffman]

To catch an egg? A bucket of water.

 

[BvU]

Hello Maddyk, and welcome to PF !

An egg is incredibly strong. Just try to squeeze one by applying manual pressure from all around (if you hand is big enough). No chance. But a prick with a pin will easily go through (*).

Here you can see eggs are strong enough to walk on.

Well, for my contraption I know I need to increase the time the egg drops in order to decrease the force impacted on its shell.

You mean you want to increase the time the egg decelerates from this 14 m/s down to 0 m/s. Douq's idea seems brilliant to me (*), but from your problem statement I conclude you have to do some more work. Like finding out how much deceleration an egg can withstand.

As for the amount of work: Actually your " V²=V(o)²+2a(d-do)=0+2(-9.8 m/s²)(-9.91 meters) " is correct. So at landing time you have V²=194 m²/s² , which is not the same as V = 194 m/s.

Bystander's advice still deserves following up: go through your equations (dimensions too) and check if they are correct.​

If you understand where your V² equation comes from, you'll know straightaway how much work your contraption has to do !
And since work can be used to lift a weight, perhaps you can even design your device to recover a nice fraction of the kinetic energy by letting the egg fall on an oversized cloth that is draped over the bucket with suitable weights hanging from the corners. See how far the weights can be lifted and check with mgh of the egg!

Have fun !

(*) [edit] I forgot: so the area that catches the egg is important, and with a water surface you are exploiting that.